I seem to remember someone saying the modelling programs are unreliable
when a wire is close to the ground. Also, there is really no way to model
the properties of "ground." It can vary in just a few feet and the moisture
content varies from day to day. I think this is a "try it" kind of antenna.
Read other's reported results.
Chuck W5PR
On Sat, Aug 24, 2019 at 12:29 PM Mike Waters <mikewate@gmail.com> wrote:
> The only way to predict the RDF and pattern is by modeling it. I don't know
> of anyone who has done this. I have a few of my .ez Beverage models in
> w0btu.com/files/ as a starting point, but I don't think that I uploaded
> everything there.
>
> There are free antenna modeling programs out there. I have only ever used
> EZNEC. Maybe someone can suggest something.
>
> 73, Mike
> www.w0btu.com
>
> On Sat, Aug 24, 2019, 12:05 PM Mikek <amdx@knology.net> wrote:
>
> > > But what did you mean by "proper pattern"?
> >
> > I should have said, the best pattern that adjusting the Inductive loads
> > will provide.
> >
> > Yes, I understand the pattern changes with frequency. What I want to do
> is
> > inductively load the antenna, so it will have the same pattern as if we
> > increased the length.
> >
> > Say I have a BOG with a length that is ideal to give me the best RDF
> > number available at say 1.8Mhz.
> > Now, I move down to 1MHz, and I inductively load it, can I get that
> same
> > RDF number?
> > ie. can I reduce the VF to make it act like the correct length?
> > What are the caveats?
> >
> > Thanks, Mikek
> >
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